Temporomandibular joints anterior disc displacement with reduction
Presentation
Bilateral temporomandibular joints pain with clicking sound on the right side when opening and closing.
Patient Data
In close position, bilateral articular discs are anteriorly displaced in relation to the bilateral mandibular condyles. These are measured by the angle formed between the junction of the posterior band of the disc and the bilaminar zone with the vertical orientation of condyle (more than 10 degrees is abnormal). The intermediate zone of the articular discs are also anteriorly displaced relative to the condyle (the intermediate zone supposed to be located between the temporal bone and the mandibular condyle in normal position).
The right anterior band of the disc appears to be rounded in appearance rather than normal biconcave shape. Right posterior band appears to be hyperintense and thickened. Left anterior band has normal biconcave shape.
In open position, the discs reduce/return to the normal position between the condyle and temporal bone. This returns movement generally produces clicking or popping noise.
The lateral pterygoid muscle attachment is normal in thickness.
No joint effusion.
No rupture of retrodiskal layers. Right superior retrodiskal layer is thickened.
No osteoarthritic changes on the condyle.
Case Discussion
MRI TMJ supports the diagnosis of bilateral TMJ dysfunction, which are bilateral anterior disc displacement with reduction. Abnormal right anterior band configuration, thickened/hyperintense right posterior band and right superior retrodiskal layers are in keeping with chronicity.
Tomas et al1 has concluded direct and indirect MR imaging signs of TMJ dysfunction:
Direct signs:
Abnormal disk morphologic features (crumpled, rounded, flat, perforated)
Abnormal disk displacement in closed mouth position (anterior displacement -most frequently observed, posterior displacement, lateral or medial displacement.
Abnormal disk movement in open mouth position (anterior disk displacement with or without reduction, stuck disk (disk remained fixed)
osteoarthritic changes of the condyle (flattening, osteophytes, erosion, sclerosis)
Indirect signs:
Large amount of joint fluid/effusion
Increased thickness of lateral pterygoid muscle attachments
Rupture of retrodiskal layers.
Unable to process the form. Check for errors and try again.